Allyson Felix (born November 18, 1985) is a track and field sprint athlete, who competes internationally for the United States, primarily in the 200 meters. She also competes at the 100 meters and the 400 meters distances. She is a two-time Olympic silver medalist at the 200 meters, as well as being the only woman ever to be a three-time Athletics World Championship gold medalist for that distance. She is also an Olympic gold medalist, winning gold at the Beijing 2008 Olympics as a member of the United States' Women's 4 x 400 meters team.
As a participant in the US Anti-Doping Agency's "Project Believe" program, Felix is regularly tested to ensure that her body is free of performance-enhancing drugs.